Manually controlled metering pump for bottles with deformable sheaths

ABSTRACT

A manually operated metering pump for a container with a flexible body, comprising a metering chamber (20) between a lower valve (21) and an upper valve (48), a spring-biased push button (34), and a nozzle communicating with the metering chamber (20) via a central channel. The lower valve (21) is flexible and frusto-conical, and the upper valve (48) is supported on a disc (47) forming the base of a hollow rod (43) secured to the push button (34), and engages the bottom of a hollow plunger (32) operated via a push button (34).

FIELD OF THE INVENTION BACKGROUND OF THE INVENTION

The invention relates to a manually controlled metering pump for bottleswith deformable sheaths.

Certain liquid or pasty products, particularly medications, are offeredin bottles and must not be exposed to the air to keep their cleanlinessor to avoid degradation. The bottles which contain them must thus have adeformable sheath, so that the volume of this sheath always correspondsto the volume of the liquid present in the bottle.

To dispense the liquid, it is known to use a screwed push button whichis raised, then return it to place. It is also known to use a manuallycontrolled pump having at its lower part an inlet ball valve and at itsupper part an outlet ball valve. The pumps of this type operatecorrectly when maintained strictly upright.

If the bottle is on its side or inclined, the balls have the tendency toleave their conical seat and the pump does not ensure satisfactorysealing of the bottle.

There is also known from Patent Abstract of Japan, Vol. 13, No. 265, ofJun. 19, 1989 and JP-1-66,475, a metering pump adapted for very viscousfluids, comprising a metering chamber between a lower valve and an uppervalve, a push button returned by a spring and a spout communicating withthe metering chamber via the central channel.

The present invention has for its object to provide a pump ensuringsealing of the bottle no matter what its position.

The invention has for an object a manually controlled metering pump fora bottle with a deformable sheath, comprising a metering chambercomprised between a lower valve and an upper valve, a push buttonreturned by a spring and a spout communicating with the metering chambervia a central channel, the upper valve being carried by a discconstituting the base of a hollow rod secured to the push button, andbearing from below on a hollow piston adapted to be driven by the pushbutton, and sliding in the metering chamber, characterized in that thelower valve is flexible, of truncated conical shape and is maintained onthe bottom of the pump by a key, in that the hollow piston has aconstriction on which comes to bear a central tube carried by the pushbutton and in that the hollow rod is enlarged below the restriction, anO-ring seal being disposed between the enlargement of the hollow rod andthe constriction.

According to other characteristics of the invention:

the hollow piston carries an O-ring to ensure sealing in the meteringchamber.

the O-ring is held in a groove carried by the hollow piston,

the groove surrounds the O-ring on three sides;

the groove maintains the O-ring from above and within it, and the O-ringis maintained from below by the edge of the disk constituting the baseof the hollow rod;

the lower valve is carried by a truncated conical portion of the bottomof the pump.

BRIEF DESCRIPTION OF THE DRAWINGS

Other characteristics will appear from the description which followswith reference to the accompanying drawing, on which can be seen:

FIG. 1--a cross-sectional view of a bottle with a deformable sheathprovided with a pump according to the invention;

FIG. 2--a cross-sectional view of the pump of FIG. 1 at the end ofpumping for expelling liquid.

FIG. 3--a cross-sectional view of a modified embodiment of a model witha deformable sheath provided with a pump according to the invention.

FIG. 4--a cross-sectional view of the pump of FIG. 3 in the course ofpumping.

DETAILED DESCRIPTION OF THE INVENTION

In FIG. 1, the bottle provided with the pump according to the inventioncomprises a rigid external sheath 1 and a deformable internal sheath 2disposed within the rigid sheath 1. The neck 3 of the deformableenvelope 2 is disposed on the neck 4 of the rigid sheath 1. A meteringpump 5 is provided on the sheaths 1 and 2 of the bottle with theinterposition of a neck joint 6. A protective cap 7 is disposed on thepump 5.

The pump 5 comprises a body 8 having an external cylindrical skirt 9adapted to have snap fitting with the exterior of the rigid sheath 1 ofthe bottle, and intermediate skirt 10 being applied to the interior ofthe deformable internal sheath 2 of the bottle, and an internal skirt11. The three coaxial skirts are carried by a flat ring 12 which bearson the neck joint 6 to compress it to ensure sealing between theinterior of the deformable sheath 2 and the exterior of the bottle.

Below the flat ring 12 is disposed a bottom 13 of the pump 5. Thisbottom 13 comprises an external cylindrical wall 14 bearing on theinterior of the intermediate skirt 10 and an internal cylindrical wall15 bearing on the interior of the internal skirt 11 of the body 8 of thepump 5. These two walls 14 and 15 are connected by a truncated conicalportion 16 that opens downwardly, and whose external edge projectsslightly relative to the external wall 14 to coact with a groovepresented by the intermediate skirt 10 so as to ensure the blocking inposition of the bottom 13 on the body 8. The truncated conical portion16 is prolonged inwardly by another truncated conical portion 17 thatopens upwardly and has a central opening 18. The truncated conicalportion 17 of the bottom 13 moreover has at least one opening 19 adaptedto place the interior of the deformable sheath 2 into communication withthe metering chamber 20 disposed above the bottom 13.

On the truncated conical portion 17 that opens upwardly, is disposed alower flexible truncated conical valve that is maintained bearingagainst the bottom 13 by a key 22 passing through the valve 21 and thecentral opening 18 of the bottom 13.

This valve 21 closes the opening 19 of communication between theinternal sheath 2 of the bottle and the metering chamber 20 of the pump.

Above the flat ring 12, the body 8 of the pump 5 has, from the exteriortoward the interior, three coaxial walls: an external wall 23 extendingin prolongation of the external skirt 9, then after a constriction 24,extending via a cylindrical portion 25 provided with an annular riboutwardly to coact with the cap 7 to ensure its holding; an intermediatewall 26, connected at least partially to the external wall 23 at itsupper portion by radial arms 27; and an internal wall 28 substantiallyat the same height as the intermediate wall 26.

At its upper portion, the internal wall 28 carries a flat ring 29 whichextends toward the axis 30 of the bottle, and is prolonged by acylindrical wall 31 extending upwardly.

This cylindrical wall 31 serves as a guide for the piston 32 of the pump5. This piston 32 is cylindrical and hollow. It has at about the middleof its height, a constriction 33 adapted to serve to bear on the pushbutton 34 of the pump 5. It carries at its base an annular enlargement35 adapted to come into bearing against the flat ring 29. Below thisenlargement 35 is disposed an annular groove 36 in which is disposed anO-ring 37 ensuring sealing against the internal wall 28.

The push button 34 is comprised essentially of a spout 38 at its upperportion, a central tube 39 and a bell 40, coaxial with the central tube39. This bell 40 has a cylindrical skirt 41 adapted to slide within theintermediate wall 26. The bell 40 is urged upwardly by a spiral spring42, which extends from the upper portion of the bell 40, to the interiorof the skirt 41 of the bell 40, toward the exterior of the internal wall28, to the flat ring 12 on which it bears.

The central tube 39 is adapted to slide within the piston 32 until itenters into contact with the constriction 33. It carries at its interiora hollow rod 43, which is secured to the central tube 39. The rod 43slides within the constriction 33 of the piston 32. It is enlarged belowthe constriction 33 and between its enlargement 45 and the constriction33 is disposed a sealing O-ring 44. Below its enlargement 45, the hollowrod 43 has lateral openings 46 adapted to establish communicationbetween the interior of the rod 43 and the exterior.

At its lower end, the rod 43 carries a disk 47 on which is disposed anupper valve 48 of annular shape, which bears below the enlargement 35 ofthe piston 32.

At the level of the lower portion of the spout 38, the bell 40 carriesexternally a ring 49. Between this ring 49 and the upper portion of theintermediate wall 26, is provided a tear-off cylindrical collar, notshown, adapted to guarantee non-use of the pump if it has not beenremoved.

When the pump 5 is at rest, it is in the position shown in FIG. 1. Thepush button 34 is in raised position, the upper valve 48 is closed, thecentral tube 39 does not bear against the constriction 33 of the piston32 but is slightly above it, the enlargement 35 of the piston 32 bearsbelow the flat ring 29, and the lower valve 21 is closed. The meteringchamber 20 is defined by the space comprised between the upper valve 48and the lower valve 21 within the internal cylindrical wall 28.

In FIG. 2, the pump 5 is shown at the end of a pumping stroke. The disk47 is in the lowered position at the level of the flat ring 12, theupper valve 48 is open, the openings 46 of the hollow rod 43 areexposed, and the product contained in the metering chamber 20 of FIG. 1has been conveyed toward the spout 38 by the central channel 50 of therod 43 of the tube 39.

Starting with the position of FIG. 1, the operation of the pumpaccording to the invention is as follows: manual pushing on the pushbutton 34 causes the central tube 39 to descend until it bears againstthe restriction 33 of the piston 32. In the course of this descent, theupper valve 48 opens and the product contained in the chamber 20commences to pass through the openings 46 of the rod 43 toward thecentral channel 50. The downward movement of the push button 34continues, driving the piston 32, which slides in the cylindrical wall31. The cylindrical skirt 41 of the bell 40 slides within theintermediate wall 26 and the spring 42 is compressed. During thedownward movement of the piston 32, the product contained in the chamber20 flows through the openings 46, the central channel 50 and the spout38.

At the end of the downward movement, manual pressure on the push buttonis released and the spring 42 causes the push button 34 to rise again,driving the rod 43 with which it is fixed. The upper valve 48 closes andthe rising of the push button 34 causes the rising of the piston 32 bythe pressure of the valve 48 below the annular enlargement 35 of thepiston 32. The lower valve 21 opens and the product contained in thedeformable sheath 2 then rising into the chamber 20, the decrease ofcorresponding volume giving rise to a corresponding deformation of thedeformable sheath 2. When the push button 34 has returned to its initialposition of FIG. 1, the lower valve 21 closes.

In the embodiment of FIG. 3, certain details are modified relative toFIG. 1. Thus, above the flat ring 12, the body 8 of the pump 5 again hasthree coaxial walls, but if the intermediate wall 26 and the internalwall 28 are identical to those of FIG. 1, the external wall 51 ismodified relative to the wall 23 of FIG. 1. The wall 51 is flared towardthe axis 30 of the pump 5 and its external edge is shaped to receive theprotective cap 7. Moreover, this wall 51 is not connected to theintermediate wall 26.

Another modification relates to the groove 36 for maintaining the O-ring37. In FIG. 1, this groove 36 surrounds the O-ring on three sides. Inthe embodiment of FIG. 3, the groove 36 maintains the O-ring 37 only ontwo sides: above and from within. The underside of the O-ring 37 ismaintained by the external edge of the disk 47 constituting the base ofthe rod 43. This arrangement permits avoiding a two-part mold for theproduction of piston 32 which carries the O-ring 37, which avoids flashat the mold joint, from the opening and closing of the mold, in thegroove of the O-ring, and thus improves the seal at this joint.

In FIG. 4, the relative positions of the O-ring 37, the groove 36 andthe disk 47 are easily visible. The disk 47 is fairly wide to drive theO-ring 37 during rising of the push button, but it lets pass aboutitself the product which flows toward the central channel 50.

The operation of the pump according to FIGS. 3 and 4 is identical tothat of the pump of FIGS. 1 and 2.

The pump according to the invention has been described in the case of abottle with a deformable wall. Its operation is identical in the case ofa bottle with a piston rising in a cylindrical sheath 2 to preserve theproduct from contact with the air.

We claim:
 1. Manually controlled metering pump for a bottle with adeformable sheath, comprising a metering chamber disposed between alower valve and an upper valve, a push button urged by a spring and aspout communicating with the metering chamber via a central channel, theupper valve (48) being carried by a disk (47) constituting the base of ahollow rod (43) secured to the push button (34), and bearing below ahollow piston (32) adapted to be driven by the push button (34), andsliding in the metering chamber, characterized in that the lower valve(21) is flexible, of truncated conical shape and is maintained on thebottom of the pump by a key, in that the hollow piston (32) carries aconstriction (33) onto which comes to bear a central tube (39) carriedby the push button (34), and in that the hollow rod (43) is enlargedbelow the constriction (33), a sealing O-ring (44) being disposedbetween the enlargement (45) of the hollow rod (43) and the constriction(33).
 2. Pump according to claim 1, characterized in that the hollowpiston (32) carries an O-ring (37) to ensure sealing in the meteringchamber.
 3. Pump according to claim 2, characterized in that the O-ring(37) carried by the hollow piston (32) is held in a groove (36) carriedby the hollow piston (32).
 4. Pump according to claim 3, characterizedin that the groove (36) surrounds the O-ring (37) on three sides. 5.Pump according to claim 3, characterized in that the groove (36)maintains the O-ring (37) from above and from within, and from below theO-ring is maintained by the edge of the disk (47) constituting the baseof the hollow rod (43).